Sources: iPhone5, iPhone5 with V-MODA Verza and Beyerdynamic A200p DAC/amps, various computers using the Microstreamer and FiiO E07k DAC/amps.

Review note: My first impressions of the sound of the HD-26 are based on direct comparisons to other headphones - the v-moda M80 and M100, the Beyerdynamic DT1350 and T51p, the FAD Pandora IV and VI, and notes I've accumulated from many prior reviews. I describe how I relate to the HD-26 (i.e. my personal tastes and how I use the headphone) only after covering all of the objective issues.

When I first heard the HD-26, my impression was of a fairly neutral sound, but with good bass support. The treble is on the shy side of shy-neutral (a term I use to describe an ideal treble that's not nearly as strong as the Sennheiser HD800), which means it doesn't reproduce treble sounds or upper harmonics as accurately as it should. This isn't merely a matter of how strong the treble is (the HD-26 treble is weak), but it's also a matter of colorations that are partly cloaked by the weak treble. The significant colorations are obvious with test tones - a sudden recess at 5 khz and another around 9 khz. When those are fixed, the sound is superb top to bottom (since the bass is excellent) and the soundstage** opens up convincingly. The HD-26 is efficient enough to work well with cellphones and other such portable music players, but using an external amp from a Line Out or digital output makes a big difference in sound quality. This is especially noticeable with the resolution that the HD-26 provides.

**The notion that a closed headphone's soundstage is greatly narrowed by the simple colorations described here is not well known in the audiophile community, but simply fixing those colorations with a couple of narrow-band adjustments opens up the soundstage, along with the space and air that most users are missing but don't realize they can restore.

The HD-26 reminds me of the Sennheiser Amperior in some ways - not in others. The modular construction and split headband are reminiscent, but the HD-26 headband always splits wide open on my head, and when I press it back together it just splits wide open again. It's comfortable and the headband splitting is not a problem indoors, but tends to interfere with hats outdoors. One thought I had was that the HD-26 Pro was designed for indoor pro use only, but the ~5.5 foot straight cable and miniplug** termination suggests regular consumer use.

**The HD-26 comes with a screw-on 1/4 inch (6.35 mm) adapter, but the screw-on types aren't very secure and I recommend snap-on adapters for serious use.

The HD-26 is fairly light for its size, and being mostly plastic probably helps keep the weight down. The plastic however is very good plastic, construction and finish quality is excellent, and I read 'Made in Germany' on the bottom of the right earcup. I'd like to say here that I'm highly impressed by the look and feel of this headphone, and I hope to see more like this. The earpads are the best I've ever had for on-ear fit and comfort - they're very similar to the Beyerdynamic T51p earpads. The headband pads and the way they wrap around the headband look just like the Beyerdynamic DT1350 'Facelift' version, which has me wondering if there's some shared technology there. The earcups have about a plus/minus 10 degree lateral rotation and a typical vertical rotation, so they will likely fit anyone's ears perfectly. Since the earpads are very plush with plenty of 'squish' depth, they should conform to nearly anyone's outer ears.

The headband clamp is strong enough to keep the headphone secure without a tendency to shift with head movements, or even tilting the head up and down, but the clamping force seems to disappear almost immediately because of the very soft earpads and headband pads. The earcups can be pulled down and the headphone worn around the neck for hours when not listening, and the earcups won't bump anyone's chin like some headphones do, so I highly recommend the HD-26 as a walk-around portable. Two caveats: The earcups are deep and they don't fold flat, so when wearing around the neck those earcups will stick out some. The second caveat is the fact that on one's head, the headphone looks very bulky, somewhat like the "spaceman headgear" effect. It's illusory though, since when the earcups are pushed up toward the headband, you can hold the headphone in hand and appreciate its relatively compact size and light weight.

The HD-26 doesn't have a stiff carry case for protection, but such cases with customizable foam inserts are available online. The cable is thick enough to suggest durability - 5.5 feet long and single-entry, and connected to the left earcup with a proprietary connector. The terminator is a 3.5 mm miniplug with a 1/4 inch (6.35 mm) adapter. Isolation is above average for closed headphones, and leakage is so low that when using in a quiet office next to other workers, playing music loudly, nobody is likely to hear it. The music tracks below have been listed in a number of prior reviews, and are a selection of my most revealing tracks for headphone testing. Since these tracks cover a wide range of genres and were selected from my tests of very different headphones, there won't be a bias toward the HD-26 with this music. I'd suggest that instead of reading each comment below as an absolute, you could compare these notes to the prior reviews and see how the HD-26 compares with each individual track.

Animotion - Obsession (1980's New Wave/Techno): The upper bass synth has excellent detail and tone, and both male and female vocals sound natural, without favoring either. The HD-26 plays this very well.

Bauhaus - Bela Lugosi's Dead (~1980): Strong midrange sound effects - this is a good worst-case test for resonant-type sounds in the most sensitive midrange area. Handled very well by the HD-26.

Beethoven Symphony 9, Solti/CSO (1972): Excellent overall sound. Of special note for the HD-26 are the bass impacts beginning around 10:30 of the fourth movement. Those impacts won't astound you since they're fairly soft and in the background, but you can feel some of the weight they carry.

Black Sabbath - Iron Man (Classic Rock): Excellent instrumental detail - the vocal sounds very natural and the opening drum strikes have more impact than with any of my other headphones. As with most classic rock tracks, there is very little or no deep bass. The HD-26 plays this music very smoothly, and the lack of deep bass doesn't unbalance the treble.

Boz Scaggs - Lowdown (1976): Good sound quality - this is a great test for any nasality in the midrange. Handled well by the HD-26.

Cantus - Danny Boy (Traditional/Male Choral/Acapella): The HD-26 plays the voices with enough low end warmth and weight to sound very natural, yet there is no exaggeration of the lower register of the male voices on this track.

Cath Carroll - Moves Like You (1980's New Wave/Techno): This track's percussion and voice are crisp and well-balanced, and there's a good sense of space or soundstage around the voices and instruments. The HD-26 reproduces the space and detail convincingly.

Catherine Wheel - Black Metallic (~1991): Goth with industrial overtones - I like this since it's a great music composition and the sound effects are smoothly integrated into the mix. This may sound distorted or mushy with some headphones, but the HD-26 renders the deliberate instrumental distortions clearly.

Chris Isaak - Wicked Game (Pop/Rock): The HD-26 plays this high treble energy recording very smoothly - the voice and instruments are detailed but not sharp or edgy.

Chromatics - I'm On Fire (Synth-Pop, female lead): This track has a good amount of space around the voice and instruments, making for a very pleasant stereo image. The voice is excellent, but the tambourine isn't clearly identifiable as such.

David Hazeltine - Fur Elise (Jazz): A very high-quality recording from HDTracks. The HD-26 reproduces the instruments smoothly with a spacious ambiance. The wire-brush-on-cymbal harmonics are extended but shy on detail.

Grieg (Beecham-Royal Philharmonic) - Peer Gynt-Solveig's Lullaby (Classical): This very old (late 1950's) stereo recording must have been made on the most expensive gear in the world, since the overall sound quality and especially Ilse Hollweg's amazing voice are as close to "being there" as I've heard with some of the better classical recordings made since the year 2000. The HD-26 plays this music very well.

Hans Zimmer - Dark Knight-Aggressive Expansion (Soundtrack): The percussion in this track hits really hard, and the bass tones beginning around 0:45 have the ultra-deep "shuddery" kind of sound and feel that indicates an excellent deep-bass response. Overall, the HD-26 plays this music very well.

Hugo Audiophile - 15-16 (Electronic): I'm not sure what the 15-16 stands for - perhaps track numbers from a CD album. The strong deep-bass tones that start around 33-34 seconds into the track reproduce extremely well with the HD-26. This is a great recording for evaluating whether a headphone's bass will be sufficient for most environments, since for many headphones that have a weaker bass, the deep bass gets absorbed and mostly lost when the environment contains a lot of low-frequency energy.

Jimmy Smith - Basin Street Blues (early 60's): This track has several loud crescendos of brass and other instruments that don't sound clean and musical with some headphones. The HD-26 provides adequate reproduction. Listen particularly to the second crescendo at 15 seconds in for maximum detail effect. I'd like to emphasize that these crescendos are probably the worst-case test I have for instrumental separation and detail, and the HD-26 plays them with no obvious distortion.

Kellogg Auditorium, Battle Creek Michigan, Aeolian-Skinner Organ (1933) - Pedal, 32', Resultant, Arpeggio: This 16 hz organ pedal tone differs from other music tones in that you won't "hear" the tone - you'll only feel it. Although most music tones have harmonics (including this one), the harmonics from this tone will be too weak to provide any "feel", so whatever you actually hear would not be part of the fundamental 16 hz tone. There are ~30 hz sounds in the outdoor environment in big cities, generated by large trucks, buses, and subway trains, and they have a quality of "rumble" that's similar to some deep-bass tones found in music. This 16 hz organ tone is easily distinguished from those sounds when compared on a headphone that has good undistorted response at 16 hz. The HD-26 plays this fairly well, which is to say that you can feel some of the fundamental tone.

Michael Tilson Thomas - Rhapsody In Blue (20th Century Classic): Great sound and soundstage, and terrific piano playing and tone. There are some very deep bass impacts starting around 38 seconds into the 17:24 length track, and the weight of those impacts is subtle but appreciable with the HD-26.

Phaeleh - Afterglow (feat. Soundmouse) (Electronic/Vocal): The instrumental sounds that begin this track are played very nicely by the HD-26, but the voice tends to overwhelm those background sounds - until the heavy bass impacts kick in. If there is any doubt about whether the HD-26 will play heavy impactful bass with good detail (if such sounds are really in the recording), this track is the proof. If you were to begin your HD-26 listening with this track, you might think you were listening to a headphone that has a boosted but tight and detailed bass. Simply amazing.

Porcupine Tree - Trains (Pop-Rock): This track opens with some nicely-detailed string sounds and a forward-sounding male voice with a higher-than-average register. There are a series of "clip-clop" effects starting at 3:19 that may lack clarity and proper harmonic detail on some headphones, but the HD-26 makes those effects sound natural.

Richard Strauss (Mester-Pasadena) - Also Sprach Zarathustra (opening) (Classical): The granddaddy of bass is in the opening 1:50 of this recording, and I've heard it only once on a large and expensive loudspeaker system in Cleveland. For most people, that experience would be indistinguishable from being in a fairly strong earthquake. The HD-26 conveys as much of that experience as is possible on a more-or-less neutral headphone. The tympani also have good impact here.

Scarlatti-Kipnis - Sonata in E Major K381 (Classical, Harpsichord): The harpsichord here is fairly bright and detailed, but the tonal harmonics are slightly veiled and the transients are soft.

Trombone Shorty - Backatown (Jazz-Funk): The deep bass impacts here are unusually strong, and work very well with the horns and other instruments. The HD-26 delivers the impacts with proper weight and detail, and the horns have the kind of bite that gives them a realistic sound.

William Orbit - Optical Illusion (Billy Buttons Mix) (Electronic): This is about as close as I want to get to easy-listening music. The string tones beginning at 0:18 are fairly soft, and while the bass isn't very deep, it still adds a good underpinning to the music. The short poetic rap at 4:14, preceded by an etherial female voice, works very well with this track.